In a procedure of manufacturing a thin film transistor (TFT) substrate, it is required to deposit Al, Mo, Ti, Cu and other metal films, and ITO, IGZO and other non metal films on a glass substrate. The manufacturing procedure is usually achieved by using a physical vapor deposition (PVD) machine. The working principle of PVD is to use Ar ions in a plasma to bombard a target material for sputtering the atoms of the target material and transferring the atoms to a surface of the glass substrate, to complete the deposition of a film layer. According to the requirements in depositing the film layer, a corresponding target material is mounted to a machine. With the passing of time, the target material is consumed unremittingly. Currently, the completion of the consumption of the target material on the machine cannot be found out in time, which may easily cause the situation of the breakdown of the target material, and thus influence the backboard and the product. In order to prevent the occurrence of this situation, it is required to master the consumption condition of the target material in time.
It is necessary to provide a novel apparatus and a novel method for film formation by physical sputtering so as to solve the above-mentioned problem.